Revert "Update Chrome & Chromedriver to version 85 in the QA image"

This reverts commit 3c624f1e since it
caused failures in the QA and performance jobs:
https://gitlab.com/gitlab-org/gitlab/-/issues/246903.
Signed-off-by: Rémy Coutable <remy@rymai.me>

qa/Dockerfile

@@ -3,8 +3,8 @@ LABEL maintainer="GitLab Quality Department <quality@gitlab.com>"
 
 ENV DEBIAN_FRONTEND="noninteractive"
 ENV DOCKER_VERSION="17.09.0-ce"
-ENV CHROME_VERSION="85.0.4183.83-1"
-ENV CHROME_DRIVER_VERSION="85.0.4183.87"
+ENV CHROME_VERSION="84.0.4147.89-1"
+ENV CHROME_DRIVER_VERSION="84.0.4147.30"
 ENV CHROME_DEB="google-chrome-stable_${CHROME_VERSION}_amd64.deb"
 ENV CHROME_URL="https://s3.amazonaws.com/gitlab-google-chrome-stable/${CHROME_DEB}"